If you are concerned about getting enough calcium without cheese or dairy in general, there are many plant sources of calcium, and fortified foods. There are a ton of plant milks out there now. The most commonly found is soy milk, followed by almond milk. Others include rice milk, hemp milk, oat milk, coconut milk. Some types of leafy greens with a low oxylate content (oxylates block absorption of calcium) are very high in calcium such as collard greens, kale, bok choy, broccoli. They are great in salads, smoothies, soups, sandwiches, casseroles, even as wraps. White beans, sesame seeds, chia seeds, blackstrap molasses, figs, and fortified foods such as energy bars, dairy free yogurts, and some orange juices are good sources of calcium also.
I like to use hummus on top of homemade pizza in place of cheese. But on occasion I use Daiya nondairy "cheese" shreds or slices. I have also made my own "cheese" sauce to go over baked potatoes by blending a steamed sweet potato, tofu, a little bit of nutritional yeast, some almond milk, and spices. It is rich, creamy, and nutritious! Nutritional yeast is an inactivated form of yeast that has a nutty cheesy like flavor to it and works for making "cheese" types of dishes. It does not taste just like cheese but is very good in it's own way. There are also nut based cheeses out there but they tend to be more expensive. I have made my own nut based cheese.
Once you begin to explore all the possibilities of a plant based diet, you won't miss cheese at all! There are just so many cookbooks and blogs out there full of recipes and ideas that do not include cheese! Check out Post Punk Kitchen, or Oh She Glows, or Vegan Dad, or VegWeb. Check out your local library for vegetarian and vegan cookbooks. Vegetarian cookbooks often include dairy in them, but not always. There is a site called "Dairy Free Cooking" online that includes dishes and recipes with eggs but not dairy if that is something you are looking at.